What's surprising there is how big it seems "Star Wars fans" actually are when it comes to this film's reception. Up until this article, I'd assumed there were lots of repeat views, but they were a) only two on the regular and b) mostly newcomers or casuals. This is kinda what people assumed got Titanic as many tickets sold as it did: A whole bunch of people going back and seeing it a second/third time, with a much smaller percentage going back 5-6 times.
I mean, that might still be the case, but it seems way easier to paint the picture that existing fans are really pushing this film up the box-office charts, now. Which sorta reinforces how important it is that this film does create new Star Wars fans. Because normally, relying solely on a pre-existing fanbase to get your film tasting some of that rareified air is a bad, bad call.
edit: Although, what I just wrote sorta unfairly assumes Star Wars fans are the lion's share of repeat views, and they're simply going back because it's Star Wars, as opposed to the idea it's just a very rewatchable film, and both old and new fans would like to take advantage of that fact.